Investments (Trust gain loss) (Details) - SCE - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Investments
Gross realized gains	$ 84	$ 48	$ 186	$ 243
Gross realized losses	(8)	(38)	(22)	(69)
Net unrealized gains/(losses) for equity securities	$ 31	$ (81)	$ 116	$ (17)